1. Technical Field
The present invention generally relates to a transducer for sensing some physical parameter; and more particularly to a pressure transducer for sensing pressure using a differential pressure sensing technique.
2. Description of Related Art
Cane or large diameter waveguides having a diameter of at least 0.3 millimeters have proven to be useful elements for creating highly reliable tunable grating based elements, and appear to be suitable for a variety of other applications. One primary application of interest is pressure sensing. One of the issues associated with the use of gratings for monitoring pressure is the need to include a “reference” grating to remove the extraneous effects such as thermally induced shifts in the grating wavelength. There is a need in the art to accomplish this using a grating in a cane waveguide.